Simon Rozman
ab8d37ee75
While runtime asserts also served as MSVC Code Analysis hints, the lack
of asserts in Release builds provides no hints to Code Analysis which
rises a lot of warnings then.
Maybe I should learn how to use SAL to annotate <ptr, len> parameter
pairs to allow ptr==nullptr when and only when len==0? 😇
Signed-off-by: Simon Rozman <simon@rozman.si>
162 lines
3.3 KiB
C++
162 lines
3.3 KiB
C++
/*
|
|
SPDX-License-Identifier: MIT
|
|
Copyright © 2016-2023 Amebis
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include "compat.hpp"
|
|
#include <cstdint>
|
|
#include <string>
|
|
#include <vector>
|
|
|
|
|
|
namespace stdex
|
|
{
|
|
///
|
|
/// Hexadecimal encoding session
|
|
///
|
|
class hex_enc
|
|
{
|
|
public:
|
|
///
|
|
/// Constructs blank encoding session
|
|
///
|
|
hex_enc() noexcept
|
|
{
|
|
}
|
|
|
|
|
|
///
|
|
/// Encodes one block of information, and _appends_ it to the output
|
|
///
|
|
/// \param[in,out] out Output
|
|
/// \param[in] data Data to encode
|
|
/// \param[in] size Length of `data` in bytes
|
|
///
|
|
template<class _Elem, class _Traits, class _Ax>
|
|
void encode(_Inout_ std::basic_string<_Elem, _Traits, _Ax> &out, _In_bytecount_(size) const void *data, _In_ size_t size)
|
|
{
|
|
_Assume_(data || !size);
|
|
|
|
// Preallocate output
|
|
out.reserve(out.size() + enc_size(size));
|
|
|
|
// Convert data character by character.
|
|
for (size_t i = 0; i < size; i++) {
|
|
uint8_t
|
|
x = reinterpret_cast<const uint8_t*>(data)[i],
|
|
x_h = ((x & 0xf0) >> 4),
|
|
x_l = ((x & 0x0f) );
|
|
|
|
out += x_h < 10 ? '0' + x_h : 'A' - 10 + x_h;
|
|
out += x_l < 10 ? '0' + x_l : 'A' - 10 + x_l;
|
|
}
|
|
}
|
|
|
|
|
|
///
|
|
/// Returns maximum encoded size
|
|
///
|
|
/// \param[in] size Number of bytes to encode
|
|
///
|
|
/// \returns Maximum number of bytes for the encoded data of `size` length
|
|
///
|
|
size_t enc_size(_In_ size_t size) const noexcept
|
|
{
|
|
return size*2;
|
|
}
|
|
};
|
|
|
|
|
|
///
|
|
/// Hexadecimal decoding session
|
|
///
|
|
class hex_dec
|
|
{
|
|
public:
|
|
///
|
|
/// Constructs blank decoding session
|
|
///
|
|
hex_dec() noexcept :
|
|
buf(0),
|
|
num(0)
|
|
{
|
|
}
|
|
|
|
|
|
///
|
|
/// Decodes one block of information, and _appends_ it to the output
|
|
///
|
|
/// \param[in,out] out Output
|
|
/// \param[out] is_last Was this the last block of data? Actually, is this block of data complete?
|
|
/// \param[in] data Data to decode
|
|
/// \param[in] size Length of `data` in bytes
|
|
///
|
|
template<class _Ty, class _Ax, class _Tchr>
|
|
void decode(_Inout_ std::vector<_Ty, _Ax> &out, _Out_ bool &is_last, _In_z_count_(size) const _Tchr *data, _In_ size_t size)
|
|
{
|
|
is_last = false;
|
|
|
|
// Trim data size to first terminator.
|
|
for (size_t k = 0; k < size; k++)
|
|
if (!data[k]) { size = k; break; }
|
|
|
|
// Preallocate output
|
|
out.reserve(out.size() + dec_size(size));
|
|
|
|
for (size_t i = 0;; i++) {
|
|
if (num >= 2) {
|
|
// Buffer full.
|
|
out.push_back(buf);
|
|
num = 0;
|
|
is_last = true;
|
|
} else
|
|
is_last = false;
|
|
|
|
if (i >= size)
|
|
break;
|
|
|
|
int x = data[i];
|
|
if ('0' <= x && x <= '9') {
|
|
buf = ((buf & 0xf) << 4) | (uint8_t)(x - '0');
|
|
num++;
|
|
} else if ('A' <= x && x <= 'F') {
|
|
buf = ((buf & 0xf) << 4) | (uint8_t)(x - ('A' - 10));
|
|
num++;
|
|
} else if ('a' <= x && x <= 'f') {
|
|
buf = ((buf & 0xf) << 4) | (uint8_t)(x - ('a' - 10));
|
|
num++;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
///
|
|
/// Resets decoding session
|
|
///
|
|
void clear() noexcept
|
|
{
|
|
num = 0;
|
|
}
|
|
|
|
|
|
///
|
|
/// Returns maximum decoded size
|
|
///
|
|
/// \param[in] size Number of bytes to decode
|
|
///
|
|
/// \returns Maximum number of bytes for the decoded data of `size` length
|
|
///
|
|
size_t dec_size(_In_ size_t size) const noexcept
|
|
{
|
|
return (size + 1)/2;
|
|
}
|
|
|
|
|
|
protected:
|
|
uint8_t buf; ///< Internal buffer
|
|
size_t num; ///< Number of nibbles used in `buf`
|
|
};
|
|
}
|